President Obama's "science czar," John Holdren, once floated the idea of forced abortions, "compulsory sterilization," and the creation of a "Planetary Regime" that would oversee human population levels and control all natural resources as a means of protecting the planet -- controversial ideas his critics say should have been brought up in his Senate confirmation hearings.

Holdren, who has degrees from MIT and Stanford and headed a science policy program at Harvard's Kennedy School of Government for the past 13 years, won the unanimous approval of the Senate as the president's chief science adviser.

He was confirmed with little fanfare on March 19 as director of the White House's Office of Science and Technology Policy, a 50-person directorate that advises the president on scientific affairs, focusing on energy independence and global warming.

But many of Holdren's radical ideas on population control were not brought up at his confirmation hearings; it appears that the senators who scrutinized him had no knowledge of the contents of a textbook he co-authored in 1977, "Ecoscience: Population, Resources, Environment," a copy of which was obtained by FOXNews.com.

The 1,000-page course book, which was co-written with environmental activists Paul and Anne Ehrlich, discusses and in one passage seems to advocate totalitarian measures to curb population growth, which it says could cause an environmental catastrophe.

The three authors summarize their guiding principle in a single sentence: "To provide a high quality of life for all, there must be fewer people."

As first reported by FrontPage Magazine, Holdren and his co-authors spend a portion of the book discussing possible government programs that could be used to lower birth rates.

Those plans include forcing single women to abort their babies or put them up for adoption; implanting sterilizing capsules in people when they reach puberty; and spiking water reserves and staple foods with a chemical that would make people sterile.

To help achieve those goals, they formulate a "world government scheme" they call the Planetary Regime, which would administer the world's resources and human growth, and they discuss the development of an "armed international organization, a global analogue of a police force" to which nations would surrender part of their sovereignty.

Holdren's office issued a statement to FOXNews.com denying that the ecologist has ever backed any of the measures discussed in his book, and suggested reading more recent works authored solely by Holdren for a view to his beliefs.

"Dr. Holdren has stated flatly that he does not now support and has never supported compulsory abortions, compulsory sterilization, or other coercive approaches to limiting population growth," the statement said.

"Straining to conclude otherwise from passages treating controversies of the day in a three-author, 30-year-old textbook is a mistake."

But the textbook itself appears to contradict that claim.

Holdren and the Ehrlichs offer ideas for "coercive," "involuntary fertility control," including "a program of sterilizing women after their second or third child," which doctors would be expected to do right after a woman gives birth.

"Unfortunately," they write, "such a program therefore is not practical for most less developed countries," where doctors are not often present when a woman is in labor.

While Holdren and his co-authors don't openly endorse such measures on other topics, in this case they announce their disappointment -- "unfortunately" -- that women in the third world cannot be sterilized against their will, a procedure the International Criminal Court considers a crime against humanity.

Click here to see the passage on sterilizing women | Click here for the full section on "Involuntary Fertility Control"

"It's very problematic that he said these things," said Ben Lieberman, a senior policy analyst at the Heritage Foundation. Lieberman faulted Holdren for using government as a solution to every problem and advocating heavy-handed and invasive laws.

But other members of the scientific community said accusations against Holdren are wholly misplaced.

"John Holdren has been one of the most well-respected and prominent scientific voices urging the federal government to address global warming," wrote Kevin Knobloch, president of the Union of Concerned Scientists, in a statement.

Holdren's co-authors, Paul and Anne Ehrlich, said in a statement that they were "shocked at the serious mischaracterization of our views and those of John Holdren," caused by what they called misreadings of the book.

"We were not then, never have been, and are not now 'advocates' of the Draconian measures for population limitation described -- but not recommended" in the book, they wrote.

Still, William Yeatman, an energy policy analyst at the Competitive Enterprise Institute, faulted the Senate for not screening Holdren more strenuously during his hearings before confirming his nomination by unanimous consent both in committee and in the full Senate.

Despite "the litany of apocalyptic warnings that turned out to be incorrect, no one was willing to stick his neck out" and vote no, Yeatman said.

Some of Holdren's views on population came under fire during the otherwise quiet confirmation hearing before the Senate Committee on Commerce, Science, and Transportation, where Sen. David Vitter, R-La., asked him to revisit his past statements about environmental catastrophes that have never come to pass.

"I was and continue to be very critical of Dr. Holdren's positions -- specifically his countless doomsday science publications and predictions that have been near universally wrong," Vitter told FOXNews.com.

"I wish that the Commerce Committee had taken more time to evaluate his record during his nomination hearing, but like with everything else in this new Washington environment, the Democratic majority and the White House were pushing to speed his nomination along," Vitter said.

Vitter grilled Holdren during the hearing, asking him to clear up his 1986 prediction that global warming was going to kill about 1 billion people by 2020.

"You would still say," Vitter asked, "that 1 billion people lost by 2020 is still a possibility?"

"It is a possibility, and one we should work energetically to avoid," Holdren replied.

Sen. John Kerry, a leading Democrat on the committee, said the renewed scrutiny was essentially a Republican smear on Holdren's good record. Kerry told FOXNews.com that senators already had "ample opportunity" to question Holdren, who "made clear that he does not and never has supported coercive approaches, end of story.

"The Commerce Committee and the Senate then unanimously concluded what I have long known -- that John Holdren is a leading voice in the scientific community and we are fortunate to have him lead the fight to restore the foundation of science to government and policymaking that has been lacking for almost a decade."

Holdren has confronted a number of challenges during his four-decade scientific career, including nuclear arms reduction, and was part of a group that shared the 1995 Nobel Peace Prize "for their efforts to diminish the part played by nuclear arms in international politics," as the Nobel Committee said.

Now his greatest focus is global warming, which he said in a recent interview poses a threat akin to being "in a car with bad brakes driving toward a cliff in the fog."

Holdren told the Associated Press in April that the U.S. will consider all options to veer away from that cliff, including an experimental scheme to shoot pollution particles into the upper atmosphere to reflect the sun's rays and cool the earth, a last resort he hoped could be averted.

"Dr. Holdren is working day and night for the Obama Administration and the American people, helping to develop science and technology policies to make the country stronger, more secure, and more energy independent, and to make Americans healthier and better educated," his office told FOXNews.com.

Four months after Holdren's confirmation, his critics are keeping a wary eye on his work in the White House, where they assert that he has the president's ear on scientific issues.

"It is interesting that this 30-year-old book is finally coming to light," said Lieberman, of the Heritage Foundation.

"The people who are concerned about Holdren, quite frankly we didn't do enough homework."